Jimmy Harkin, 57, spent time in three jails for leaving a ticking device outside the benefits office which axed his payments.

The grandad-of-two, who was released from jail in June last year, told Daily Star Online the three prisons were "powder kegs waiting to explode" with lags "regularly tripping" and staff "didn't believe" an inmate had collapsed.

INSIDER: Jimmy Harkin told how prisons are like 'powder kegs waiting to explode'

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“To be quite honest with you, I think prisons have been like a powder keg waiting to explode for a while”

Jimmy Harkin

Speaking to the Daily Star Online, the dad, of Middleton, Greater Manchester, said: "Dale Cregan, the guy who killed two police officers with hand grenades was in HMP Risley when I was there. There were a lot of paedophiles as well.

"There was a lot of weed going around and Spice, the legal high. It was crazy. You had people regularly tripping, freaking out on drugs. Prisoners were often stoned. To be quite honest with you, I think prisons have been like a powder keg waiting to explode for a while.

"I don’t know the drugs were smuggled in."

The widower witnessed an inmate collapse in jail because he was stoned and said it goes on "more often than people think". The man later "died" on the way to hospital.

But staff, Mr Harkin claimed, ignored concerns the criminal was ill.

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He continued: "It was disturbing to be quite honest because I had never seen anything like that. There was a few of us and it shocked us.

"I don’t know much he took, but it must have been a lot of drugs.

"I was on the landing when it happened. I was one of the prisoners who told staff it had happened. They said ‘there’s nothing wrong with him’ but I told them there was foam coming out of his mouth and it’s serious.

"The person who collapsed was a bit of a prankster, so staff thought he was joking.

"He ‘died’ in the ambulance on the way to hospital. They managed to revive him and bring him back.

"He came back from hospital and got to the prison and his first words to us was ‘has anybody got any stuff for me’. It was a bit stupid really."

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Mr Harkin, who is originally from Belfast, Northern Ireland, said staff in at HMP Manchester were "verbally abusive".

He added: "When I was at Strangeways in Manchester, I worked at the workshop there. We got left in a cage in the p****** rain while the kiddy fiddlers and that got let out first, which I think is wrong.

"There was a cage outside the workshops, outside. You waited there before you got let to go back to your wings. They left us out in the rain and the snow and all sorts of c***.

"Considering we worked in the workshops, you’d think we’d get priority. It wasn’t very nice.

"The paedophiles got treated better than us. We should have got priority."

Darryl Birch, 41, did time in HMP Featherstone in Staffordshire, for drug offences.

He told Daily Star Online: "The conditions of the prison are disgusting.

"You get all sorts of drugs inside, everything. I think all the people get stoned. It is so easy to get cannabis.

"The staff shortages are to blame. They are mad. I don't see it changing though.

"You get fights, a lot of the time with weapons. This is not just occasionally, I mean quite often. It's usually gang-related.

"There are people I met inside who have re-offended again and again. They prefer it inside. A lot of offenders get released but just go straight back inside. That can't be right.

"I wasn't surprised to hear of all these riots and people escaping. It has been coming really."

A Prison Service spokesperson said: “We have announced a major shake-up of the prison system with 2,500 extra prisons officers and new security measures to tackle drones, phones and drugs and help make prisons places of safety and reform.

“The Justice Secretary has always been clear that it will take time to address these long-standing problems and we must grip the real challenges and risks that we face in the shorter term.

“That is why we have taken action and set up a new prisons task force to manage down potential flashpoints of unrest in prisons, as well as a new £3m national intelligence hub to target gang crime behind bars.”